It was a terrible battle. The most dreadful of all Bilbo’s experiences, and the one which at the time he hated most—which is to say it was the one he was most proud of, and most fond of recalling long afterwards, although he was quite unimportant in it. Actually I may say he put on his ring early in the business, and vanished from sight, if not from all danger. A magic ring of that sort is not a complete protection in a goblin charge, nor does it stop flying arrows and wild spears; but it does help in getting out of the way, and it prevents your head from being specially chosen for a sweeping stroke by a goblin swordsman.

Chapter 17 The Clouds Burst